<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="lib/react.js"></script>
    <script src="lib/react-dom.js"></script>
    <script src="lib/browser.js"></script>
</head>
<body>
    

    <div  id="root"></div>

    <script  type="text/babel">



        class App extends React.Component{

            constructor(props){
                super(props)

                this.state = {
                    loading  : true
                }
            }

            componentDidMount(){

                setTimeout( () =>{

                    this.setState({
                        loading : false
                    })
                },3000)
            }

            render(){
                
                if(this.state.loading){
                    return <h1>正在加载......</h1>
                }else{
                    return (<div>
                        <h1>@@@@数据列 表</h1>    
                    </div>)
                }
            }
        }
        
        //jsx     javascript + xml  
        ReactDOM.render(<App/>,document.getElementById("root"))

    </script>
</body>
</html>